Library terminal panel

Design References

• Expression children
• Render tree contract

Contract

This feature-candidate contract depends on GX callback props and becomes usable when bus-ui implements TerminalSessionPanel.

TerminalSessionPanel renders the complete terminal surface for one session. It accepts idle, running, waiting, exited, and error states. running and waiting show stdin controls only when the onSubmit callback prop exists. exited and error disable process controls.

Prop	Required	Behavior
state	yes	idle, running, waiting, exited, or error.
sessionID	no	Stable host session identifier copied into callback payloads when present.
command	yes	Already-redacted command display string; callers remove secrets before passing this prop.
output	yes	Ordered, already-redacted TerminalChunk values rendered as escaped terminal text.
workingDirectory	no	Public-safe string shown as session metadata; hidden when omitted.
processID	no	Public-safe string shown as session metadata; hidden when omitted.
elapsed	no	Public-safe string shown as session metadata; hidden when omitted.
exitCode	no	Integer shown as session metadata; hidden when omitted.
onSubmit	no	func(TerminalSubmitEvent) gx.Result callback prop for stdin submit; omitted disables stdin controls.
onExit	no	func(TerminalExitEvent) gx.Result callback prop for requesting external process termination; omitted hides the exit control.
error	no	Public-safe error title rendered only in error state.

State behavior is deterministic: idle renders no process controls, running enables stdin when onSubmit exists, waiting shows the fixed Waiting status label and enables stdin only when onSubmit exists, and exited or error disables process controls. The exit control appears only in running and waiting states when onExit exists, so a waiting session can still request external termination.

TerminalChunk has required Stream and Text fields plus optional non-negative integer Sequence. Stream is stdout, stderr, stdin, or system. Chunks render in supplied order unless every chunk has Sequence, in which case ascending Sequence order is used with supplied order as the stable tie-breaker.

type TerminalChunk struct {
	Stream   string
	Text     string
	Sequence *int
}

Callback payloads are typed Go values. onSubmit receives a TerminalSubmitEvent with the resolved session identifier, component source, and submitted text. onExit receives a TerminalExitEvent with the resolved session identifier and component source. When sessionID is omitted, the host runtime resolves the active session from route or host context before calling the callback. If no active session can be resolved, the host does not call the callback. SourceID is the component id when present, otherwise the generated tree path for this component instance.

type TerminalSubmitEvent struct {
	SessionID string
	SourceID  string
	Text      string
}

type TerminalExitEvent struct {
	SessionID string
	SourceID  string
}

Consequence

The terminal panel renders session status, layout, controls, and deterministic output ordering. Process ownership, command execution, transport protocols, retry policy, and termination authorization stay outside the component.

UI framework index

Sources

• TerminalSessionPanel
• State UI concept